Archived posting to the Leica Users Group, 2006/11/16
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Ric, With monovision correction, the brain doesn't blend the vision from both eyes to create intermediate vision. Certainly brighter light helps to clear things up by constricting your pupil reducing coma (an optical aberration) and increasing the depth of field of your eye's optical system. If you tell your doctor where your near focus needs are located, he (she) can prescribe the best prescription lens to center the focus of the near vision eye to that distance. About a third of your brain (the back part - occipital cortex) is dedicated to processing your visual input. It's a wonderful processor with a tremendous capability to adapt to new input. It can take a few weeks before you'll feel visually comfortable after a prescription change is made in either eye. Richard On Nov 16, 2006, at 9:58 AM, Ric Carter wrote: > Hey Richard-- > > In the monovision solution, does the brain do do a "blend" to get > acceptable focus at various distances? > > Bifocals always frustrated me with their one close focal length. I > could focus easily on my monitor or book, but not on a painiting > hanging on the wall of a gallery. Bookstores and libraries were > VERY frustrating. Progressive lenses answered that for me well. > > I appreciate all the experience and knowledge you folks are sharing. > > Ric > > > > > On Nov 16, 2006, at 12:00 AM, Richard Clompus wrote: > >> Ric, >> >> As an optometrist, maybe I can shed a little light on this >> subject. :-) When you're over 40, your eyes lose their close >> focusing ability. Spectacle wearers often chose progressive (no- >> line bifocals) lenses that provide distance, intermediate and near >> focus for both eyes. There are both soft and hard bifocal contact >> lenses. Soft bifocals contacts are the most common. They contain >> multiple sets of optics that focus distance and near images >> simultaneously on the retina. Some people adapt and can ignore >> the near optics when viewing distance objects and can ignore the >> distance optics when reading. For others, they simply report >> blurred vision at distance and near. Some brains can handle this >> and some can't. The most common contact lens technique used 75% >> of the time is called monovision. You fit the dominant eye with a >> distance contact lens and the non-dominant eye with a near contact >> lens. It takes a few weeks to adapt but most people do very >> well. It's not good for some sports where depth perception is >> very important and also not good for intensive reading and near >> tasks. For many who work and drive, its the ideal compromise. >> Until we develop a focusing contact lens, monovision is the most >> common solution. With a camera, you would see the viewfinder with >> the eye wearing the distance lens. Monovision would not work if >> you have amblyopia or a "lazy eye". >> >> I hope this helps. >> >> Best regards, >> >> Richard >> >> Richard Clompus, OD >> Ponte Vedra Beach, FL >> >> >> On Nov 15, 2006, at 6:57 PM, Ric Carter wrote: >> >>> Speaking of vision adjustment-- >>> >>> Anyone here have experience with contacts for reading glasses? I >>> have a minor correction for long focus, but need reading glasses. >>> An acquaintance has a reading contact in one eye and a distant >>> contact in the other and swears it's great. >>> >>> Sounds flaky to me. >>> >>> I am, though, tired of squashing my glasses against my face to >>> focus. I'm happy with my progressive lenses otherwise after >>> finding bifocals drove me crazy in book stores and art museums. >>> >>> Ric Carter >>> http://gallery.leica-users.org/f/Passing-Fancies >>> >>> >>> >>> >>> On Nov 15, 2006, at 6:46 PM, Eduardo Albesi wrote: >>> >>>> You will not have that problem for sure: the M6 viewfinder >>>> ocular has a rubber protection to avoid glasses damage >>>> :-) >>>> >>>> Best, >>>> >>>> Ed >>>> >>>> El 15/11/2006, a las 20:32, Alastair Firkin escribi?: >>>> >>>>> I will not have that problem for a while, anything beyond arms >>>>> length is perfect, so I'll be hanging them around the neck just >>>>> above the M6 whipping them on to set up etc and then happily >>>>> shooting "raw" again ;-) >>>>> >>>>> On 16/11/2006, at 10:04, Leonard Taupier wrote: >>>>> >>>>>> Alastair, >>>>>> >>>>>> I shot with a M2 and M3 at times. If you do you better put >>>>>> something over the viewfinder to protect your glasses. It's >>>>>> metal not rubber and can be pretty sharp. I think Stephen >>>>>> still sells a little sticky donut for that purpose. What I do >>>>>> is punch a hole in a band-aid and then with scissors cut >>>>>> around the hole to fit the eyepiece. I'm still walking around >>>>>> with a scratch over the right lens the first and only time I >>>>>> didn't use protection. Just a word of advice. >>>>>> >>>>>> Len >>>>>> >>>>>> >>>>>> On Nov 15, 2006, at 6:08 PM, Alastair Firkin wrote: >>>>>> >>>>>>> I have my first pair of glasses coming this afternoon: I can >>>>>>> put up with not being able to read X-rays at work, but when I >>>>>>> could not read the f- stop on my M6 something had to give ;-) >>>>>>> Better than the alternative has always been my philosophy. >>>>>>> >>>>>>> Cheers >>>>>>> On 16/11/2006, at 7:25, Tina Manley wrote: >>>>>>> >>>>>>>> LUG: >>>>>>>> >>>>>>>> Disregard this comment that I made about the M8: >>>>>>>> >>>>>>>> "Either the viewfinder is dimmer than my M7's or my eyes are >>>>>>>> getting worse (a possibility!) It's harder to get the focus >>>>>>>> right than with the M7." >>>>>>>> >>>>>>>> I just got back from having my eyes checked and the vision >>>>>>>> in my left eye has decreased 20% since my last check-up! >>>>>>>> The doctor checked for glaucoma, cataracts, macular >>>>>>>> degeneration and all kinds of stuff and found nothing. I'm >>>>>>>> going back next week another test and some new glasses. My >>>>>>>> focusing with the M8 should improve immensely when I have >>>>>>>> glasses that match my new decreased vision. Getting old >>>>>>>> sucks but it's better than the alternative!! >>>>>>>> >>>>>>>> Tina >>>>>>>> >>>>>>>> Tina Manley, ASMP, NPPA >>>>>>>> http://www.tinamanley.com >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Leica Users Group. >>>>>>>> See http://leica-users.org/mailman/listinfo/lug for more >>>>>>>> information >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Leica Users Group. >>>>>>> See http://leica-users.org/mailman/listinfo/lug for more >>>>>>> information >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Leica Users Group. >>>>>> See http://leica-users.org/mailman/listinfo/lug for more >>>>>> information >>>>> >>>>> >>>>> _______________________________________________ >>>>> Leica Users Group. >>>>> See http://leica-users.org/mailman/listinfo/lug for more >>>>> information >>>>> >>>> >>>> >>>> >>>> _______________________________________________ >>>> Leica Users Group. >>>> See http://leica-users.org/mailman/listinfo/lug for more >>>> information >>> >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >> >> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information